Another day, another round of patent lawsuits. This time, it's Nokia (again) suing Apple (again) over infringements related to the iPhone, iPod Touch and iPad (again).

In a statement issued today, Nokia said it has filed suit against Apple in the UK, Germany and the Netherlands over the infringement of 13 patents, adding to the allegations of infringement of 24 patents by Apple filed in U.S. courts last year.

The legal battle began In October 2009 when Nokia alleged that the iPhone infringes on Nokia’s patents for GSM, UMTS and wireless LAN (WLAN) standards, specifically 10 patents that cover wireless data, speech coding, security and encryption. Then, just over a year ago, Apple fired back with a countersuit, alleging that Nokia was infringing on 13 of its patents.

It’s notable that the two sides filed those initial suits over completely different patents. Nokia sued Apple over the inner workings of the iPhone while Apple claimed that Nokia is poaching the user interface from the iPhone.

Then, at the end of December 2009, Nokia filed a complaint with the U.S. International Trade Commission, arguing that Apple “infringes Nokia patents in virtually all of its mobile phones, portable music players, and computers.” The spat focused on seven Nokia patents and Apple countered that Nokia swiped intellectual property. In a statement, Paul Melin, Nokia's VP for Intellectual Property, said:

The Nokia inventions protected by these patents include several which enable compelling user experiences. For example, using a wiping gesture on a touch screen to navigate content, or enabling access to constantly changing services with an on-device app store, both filed more than ten years before the launch of the iPhone.